Thank you, Erel. I reset my device to display larger font and tested the project with the font scaling code incorporated. What I've observed is that when I first open the app, the font sizes are large and truncated within the controls. But if I release focus of the app (without closing it) and then retrieve focus on the app, then all the fonts are re-scaled as desired.
I believe that because I am using a splash screen, it was contributing the effect described above. After I added the ResetUserFontScale(Activity) statement into the TimerSplash_End sub (as well as the keeping it in the Activity_Create sub where I already had it), I now get the desired font re-scaling in both the initial focus and when I refocus.